The present application refers to an aerodynamic covering and lining for the guiding rails of landing flaps positioned in wings of aircraft, particularly aircraft having wings of the kind in which the chamber line can be varied. On using airfoils or wings with variable camber the profile and section of the wing is changed during flight. Such a feature can be used to match lift and drag properties of the wing to the different aerodynamic conditions as they vary during flight. The purpose of this is to improve the performance of the aircraft generally and to reduce the fuel consumption in particular. Wings having variable camber cannot be equipped with the usual aerodynamic covering for the landing flaps adjusting device since on changing the camber it is inherent that relatively large uncovered gaps obtain between the wing and such a cover. Gaps in turn cause the flow conditions around the wind to deteriorate.